Device for use on zig-zag sewing machines for making carpets



Aug. 16, 1966 ESCHENKENGEL Filed May 15, 1964 DEVICE FOR USE ON ZIG-ZAG SEWING MACHINES FOR MAKING CARPETS IN VE N T 0R. EMER/CH SCHENKENGEL B Y %Mlf United States Patent 3,266,450 DEVICE FOR USE ON ZIG-ZAG SEWING MACHINES FOR MAKING CARPETS Emerich Schenkengel, Kaiserslautern, Pfalz, Germany, as-

signor to G. M. Pfaif A.G., Kaiserslautern, Pfalz, Germany Filed May 15, 1964, Ser. No. 367,761

Claims priority, application Germany, May 17, 1963,

2 Claims. (Cl. 112235) The present invention relates to zig-zag sewing machines and is particularly concerned with a device for use on machines of that type to produce carpets. The device comprises primarily a material presser foot and means for displacing the stitch area of the needle from the zero position.

It is known to produce a plush pile forming a carpet upon a fabric base by means of a zig-zag sewing machine. For this purpose special presser feet have been used of a type which were provided with a stitch tongue that extends parallel to the direction of feed. However, it is only possible with pressure feet of this type to produce carpets of the plush or Wilton type. However, for practical purposes it is very desirable to be able to produce in the same maner also carpets of the boucle type on a sewing machine. With boucle carpets the carpet pile is formed by thread loops that are closed. Since with known presser feet the stitch tongue is firmly connected at both ends with the presser foot, the closed thread loops that have been placed around the stitch tongue will no longer become free so that the closed loops cannot be drawn off of the stitch tongue. Besides, a carpet cannot be completely produced with a presser foot where the stitch tongue is fastened at both ends; primarily the border of the carpet cannot be bound. For this purpose it is necessary to sew a whipped or oversew seam or a seam that is similar, and that is not possible.

It is an object of the present invention to provide an arrangement or a device that makes it possible to produce on a conventional household machine provided with a zig-zag arrangement a plush as well as also a boucle carpet until it is fully completed. In addition to that the new device is intended to make it possible to sew patterns into the carpet pile that has already been finished, and that in a manner that the free surface of the sewn on pile pattern extends substantially flush with respect to the pile first sewn. In this connection, it is a further object of the invention to provide the presser foot with a loop rejector which after the sewing of the first bead, not only holds the pile loops aside, but also aids the seamstress in guiding the material being sewn parallel to the preceding row.

In accordance with the invention the forgoing objects are achieved in that the sole holding down the material is made L-shaped in order to hold with the one part of the L-shaped which, as seen from the position of the steamstress, is located laterally and outside of the sewing area of the needle and the other part of the L-shape is positioned in front of the sewing area so that the sewing area is only partially encompassed by the sole. Furthermore, that part of the L-shaped sole which is located ahead of the sewing area is provided with two sew-over tongues which extend with their free ends into the free space between the sewing or stitching area and the shank of the presser foot so that one of them is positioned to the left and the other to the right of the central neutral line of the stitch area to which the needle is adjusted. Thus there is an over-sew tongue located between two each of the three neutral or zero lines of the sewing area. As a terminal of the free end of the L-shape sole the invention provides a loop rejector which extends substantially parallel to the sew-over tongues and which facilitates the parallel guiding for the seamstress when she is sewing a bead alongside another head that has already been sewn.

Further objects, advantages and details of the invention will become apparent from the following specification with reference to the embodiment of the invention illustrated in the accompanying drawings, in which FIG. 1 is a perspective view of the presser foot which is required for carpet sewing; and

FIG. 2 illustrates on an enlarged scale the operations required for producing pile carpeting.

The invention is incorporated in a household sewing machine which is equipped with a zig-zag mechanism of conventional type, all parts of which must be considered as being known and which are therefore not illustrated in the drawings. The shank 1 of the presser foot intended for use with such a sewing machine is provided with an L-shaped sole 4 for holding down the material. The sole 4 comprises the legs 2 and 3. It encompasses the stitching area of the needle 5 which in zig-zag sewing machines that are equipped with means for adjusting the stitch positions is located within the reference lines xyz. The free end of the shank 3 of the presser foot terminates in a loop rejector 6.

The shank 3 is furthermore provided with three sewover tongues 7 and 8, which are rigidly fastened thereto and which are in the form of thin, flat members. The sew-over tongues 7, 8 are arranged in a manner that they are located symmetrically with respect to the center Zeno line of the sewing area and are disposed between the zero lines xy or zy of the sewing area. The thread loops 9, 10 (FIG. 2) that must be laid over the tongues 7, 8 are carried above the bottom of the sole 11 by the backs 12,

'13 of the sew-over tongues 7, 8. The backs 12, 13 here are disposed at different distances from the bottom of the sole, in particular, the back 13 of the sew-over tongue is at a distance m from the bottom and the back 12 of the sew-over tongue 7 at a distance n. Tests with yarns of different thicknesses that are suitable for the production of carpets on sewing machines resulted in determining a ratio of 1.3 to 1 as a suitable relation between m and n. For example, if a pile 21 that forms a decorative pattern is sewn onto a fabric piece 17 which is covered with pile 1 8, 19 the latter is pressed down under the presser foot and thus is held down. After sewing on the pattern pile 21, however, the pile located adjacent thereto and not covered by its raises up again so that the pattern pile that has been sewn on to a lesser loop height will provide an effect where it is flush with the pile first sewn on.

The over-sew tongues 7, 8 are extended forwardly of the shank 3 to the outer edge of the sole 14 so that between them an inlet channel 15 is formed for a seam insert 16 such as a cord.

The following sewing operations can now be carried out in a simple fashion with the device in accordance with the invention:

As the needle 5 is set to the left neutral line of the sewing area (stitch position left) or to the right neutral line (stitch position right) and is adjusted for the corresponding overstitch width, it is possible to sew thread loops over either one or the other of the over-sew tongues 7, 8 so that it becomes possible to produce carpet piles of greater or smaller height. This provides the possibility of sewing a pile 21 in the form of a decorative pattern constituted by low loops onto a pile which covers the entire fabric base 17 and that had been formed by higher loops. The sewing result obtained in this manner is surprising especially since the first sewn pile that covers the base fabric as well as also the pile 21 sewn on as a decorative pattern extend essentially to the same height above the fabric base 17, which means that a carpet having an even and plane surface is produced.

In the production of carpets of this type it is furthermore essential that the carpet borders be reinforced in order to delay any unattractive flattening caused by stepping. For this purpose it is generally conventional to sew a cord insert 16 into the seam 20 that forms the binding.

By setting the needle 5 to the center zero line of the sewing area (stitch osition center) it is possible besides sewing a straight seam that is sewn with the overstitch Width Zero while the needle passes through the two oversew tongues 7, 8 to also place thread loops 20 over both over-sew tongues for which the proper overstitch Width is set whereby the border of the material is completely bound.

FIG. 2 shows a carpet that is produced by means of the device in accordance with the invention and which consists of a fabric base 17 that has already been partly covered by sewing with boucle pile 18 and with plush pile 19. For carpets having boucle pile the loops 18 remain closed. With carpets having plush pile the sewn -loops are cut open by means of a suitable tailors tool. The cutting can be effected manually or also on the machine and that not only during the sewing operation but also after the sewing has been terminated. Upon cutting open the loops the plush pile is formed that is indicated at 19 in FIG. 2.

Having now described my invention with reference to the embodiment illustrated in the drawing, I do not wish to be limited thereto but what I desire to protect by Letters Patent of the United States is set forth in the appended claims.

I claim:

1. Device for use in a Zig-Zag sewing machine having a needle for producing carpets and comprising a presser foot disposed proximate and operatively associated with said needle and means for displacing thezero position of the stitching area of the needle, said presser foot having a shank provided with an L-s-haped presser foot sole having a free leg and extending outside of the stitching area of said needle and defining a stitching area between said presser foot shank and said free leg of said sole, said free leg having a pair of sew-over tongues extending into the area proximate said shank and adjacent the stitching area and having a loop rejector at the freely extending end thereof, in a manner that one each sew-over tongue is disposed intermediate two Zero or reference lines of the stitching area, said sole having a bottom surface and said tongues presenting backs for carrying thread loops extending to different heights above said bottom surface.

2. Device for use in a Zig-zag sewing machine having a needle for producing carpets and comprising a presser foot disposed proximate and operatively associated with said needle and means for displacing the zero position of the stitching area of the needle, said presser foot having a shank provided with an L-shaped presser foot sole having a free leg and extending outside of the stitching area of said needle and defining a stitching area between said presser foot shank and said free leg of said sole, said free leg having a pair of sew-over tongues extending into the area proximate said shank and adjacent the stitching area and having a loop rejector at the freely extending end thereof, in a manner that one each sew-over tongue is disposed intermediate two Zero or reference lines of the stitching area, said sole having a bottom surface and said tongues presenting backs for carrying thread loops extending to different heights above said bottom surface, and said sew-over tongues extending over the sole of said one leg of said L and defining above and with said one leg a channel for a seam insert such as a cord.

References Cited by the Examiner UNITED STATES PATENTS 2,481,286 9/1949 Bouwkamp et al 112-235 3,117,542 1/1964 Schenkengel 112-235 X 3,140,680 7/1964 Brenner 112-235 X FRANK J. COHEN, Primary Examiner.

P. D. LAWSON, Assistant Examiner. 

1. DEVICE FOR USE IN A ZIG-ZAG SEWING MACHINE HAVING A NEEDLE FOR PRODUCING CARPETS AND COMPRISING A PRESSER FOOT DISPOSED PROXIMATE AND OPERATIVELY ASSOCIATED WITH SAID NEEDLE AND MEANS FOR DISPLACING THE ZERO POSITION OF THE STITCHING AREA OF THE NEEDLE, SAID PRESSER FOOT HAVING A SHANK PROVIDED WITH AN L-SHAPED PRESSER FOOT SOLE HAVING A FREE LEG AND EXTENDING OUTSIDE OF THE STITCHING AREA OF SAID NEEDLE AND DEFINING A STITCHING AREA BETWEEN SAID PRESSER FOOT SHANK AND SAID FREE LEG OF SAID SOLE, SAID FREE LEG HAVING A PAIR OF SEW-OVER TONGUES EXTENDING INTO THE AREA PROXIMATE SAID SHANK AND ADJACENT THE STITCHING AREA AND HAVING A LOOP REJECTOR AT THE FREELY EXTENDING END THEREOF, IN A MANNER THAT ONE EACH SEW-OVER TONGUE IS DISPOSED INTERMEDIATE TWO ZERO OR REFERENCE LINES OF THE STITCHING AREA, SAID SOLE HAVING A BOTTOM SURFACE AND SAID TONGUES PRESENTING BACKS FOR CARRYING THREAD LOOPS EXTENDING TO DIFFERENT HEIGHTS ABOVE SAID BOTTOM SURFACE. 